Energy from Fleischmann-Pons experiments: How does it work?

1. Energy from Fleischmann-Pons experiments: How does it work? Peter L. Hagelstein Research Laboratory of Electronics Massachusetts Institute of Technology

2. Outline • Relevant experimental results • Constraint on energetic particle emission • Fractionation of a large quantum • Coherent energy exchange • Two-laser experiment • Karabut experiment • Proposed mechanism • Conclusions

3. Electrochemical cell

4. Excess energy in F&P expt 4 MJ observed during 80 hours Get 1.2 kJ for detonation of equivalent cathode volume (0.157 cc) of TNT Effect not chemistry! M Fleischmann et al, J Electroanalytical Chem 287 293 (1990)

5. But why no support for the technology? • Experiments point to new disruptive technology • No place in nuclear physics, condensed matter physics for excess heat effect in Fleischmann-Pons experiment • If known physics rules out effect, easy to argue that experimental error involved • No support available for research and development on new technology deemed inconsistent with known physics • Clarification of mechanism could help move things forward

6. Constraints on energetic 4He Observations of 4He correlated with excess energy are consistent with a Q value (energy/He atom ratio) near 24 MeV Important since mass difference between two deuterons and 4He is 24 MeV 2M[d]c2 – M[4He]c2 = 23.85 MeV If we suppose a reaction of the form Then we could gain information about what X is by measuring the kinetic energy of the 4He

7. How to measure a energy? • 4He doesn’t go very far, and loses energy in PdD, D2O • Hard to detect directly • Propose indirect detection! When 4He hits deuterons can get primary and secondary neutrons • And neutrons can be measured outside of the cell • But wait, neutron measurements have been done on cells producing excess power!

8. Yield/energy for secondary neutrons P. L. Hagelstein, Naturwissenschaften (2010)

9. What can we conclude? • 4He is born with a very low energy (less than 20 keV out of 24 MeV); result similar for upper energy of t in tritium production (less than 12 keV) • Can rule out all Rutherford picture reactions with two-body final states (lowest 4He energy is about 76 keV for recoil with gamma or electron) • If we add the practical constraint that energetic electrons and gammas would have been detected if created in amounts commensurate with the energy produced, then the constraint is much more severe • If 24 MeV shared with deuterons, then sharing must involve more than 24,000 deuterons to be consistent with upper limit near 0.01 neutron/J • Can rule out all Rutherford-picture mechanisms as inconsistent with experiment

10. Impact on theory • This result has a dramatic impact on theory! • Can rule out nearly all proposals, as only a few can be consistent with these constraints • Only three approaches left: • Transfer reaction energy to condensed matter mode • Find new mechanism to slow down energetic MeV particles without observable products • Find new mechanism for collective reaction that shares energy with more than 24,000 nearby deuterons

11. The theoretical problem • Nuclear system involves large (MeV) energy quanta • Condensed matter system involves small (meV) energy quanta • Not easy to exchange energy coherently between systems with mismatched energy quanta • But experiments seem to indicate that it happens

12. New model for fractionation of a large quantum Lossy spin-boson model: Macroscopic excited mode Two-level systems Loss near DE

13. Letts 2-laser experiment D. Letts, D. Cravens, and P.L. Hagelstein, LENR Sourcebook Volume 2, ACS: Washington DC. p. 81-93 (2009).

14. Excess power with 2 lasers In single laser experiments, excess heat turns off when laser turns off; in two-laser experiments, excess heat stays on

15. What oscillator modes? Results from dual laser experiments of Letts, J Cond. Mat. Nucl. Sci. 3 59,77 (2010)

16. Dispersion curve for PdD PdD Operation was predicted on compressional modes with zero group velocity

17. Coherent energy exchange between phonons and nuclei • Can we study effect in isolation? • Excite compressional vibrational mode strongly • Coherent energy exchange between mode and nuclei • Would be easiest for lowest energy nuclear excitation • If interaction with mode uniform in space, then nuclei excited in phase, would expect collimated x-ray emission (linear phased array effect) • So, which nuclei are best candidates?

18. What are lowest energy nuclear transitions?

19. 1.5 keV collimated x-rays in Karabut experiment (ICCF10,11) Pinhole camera x-ray image of cathode

20. Interpretation and model • Propose interpretation of Karabut experiment: • Discharge turn off causes excitation of compressional vibrational mode • Highly-excited mode couples to strongly-coupled nuclear transition • Allows weakly-coupled transition in 201Hg to be excited • In-phase excitation leads to phased-array effect collimation • Consistent with Karabut experiment if 201Hg taken to be weakly coupled to oscillator, and second transition strongly coupled • Can only get consistency for phonon exchange in association with nuclear configuration mixing

21. Proposed mechanism for excess heat production • Need to arrange for highly excited vibrational mode • Need to arrange for vacancies in Pd (or Ni, or other metals) • Need to load to create molecular D2 (or HD) near vacancies • Highly excited phonon mode plus interstitial D causes mixing of vibrational and nuclear (3S and 1D states) degrees of freedom • If insufficient D, then highly excited phonon mode causes mixing of vibrational and nuclear (host Pd, Ni, etc) degrees of freedom • D2 interacts to make 4He (or HD to make 3He), with energy to vibrational mode • Need to remove helium (high temperature helps diffusion)

22. “Clean” vs “dirty” operation • Operation with interstitial D and optical phonon mode excitation in the model results in little excitation of host nuclei, get 4He and little else • Acoustic mode operation in the model results in mixing with host lattice nuclei to allow D2/4He and HD/3He transitions, but now can excite long-lived states that decay by disintegration • So PdD (and other metal deuterides) can run “cleanly” based on optical phonon excitation in the model • And NiH (and other metal hydrides) expected to run “dirty” based on acoustic phonon excitation in the model • PdD (and other metal deuterides) can run “dirty” if acoustic phonon mode excitation used, but can get energy boost from induced fissions

23. Take away message I • Large amounts of energy production observed in Fleischmann-Pons experiments • Absence of commensurate energetic nuclear radiation indicates that fundamentally new physical process involved • Only viable theoretical approach is for coherent energy exchange with quantum fractionation • Karabut experiment seems to show effect in isolation • Letts 2-laser experiment seems to show effect for excess heat production

24. Take away message II • Theoretical models constructed which predict/explain coherent energy exchange with fractionation of large quantum • Models require highly excited vibrational mode • In Fleischmann-Pons experiment, molecular D2 transitions to 4He, energy goes into optical phonon models according to model • In Piantelli experiment, molecular HD transitions to 3He, energy goes into acoustic phonon modes according to model • Acoustic mode operation according to model leads to inadvertent excitation of long-lived fission unstable states of host nuclei, causing substantial induced disintegration (with energy loss in NiH, and energy gain in PdD)